Following the preprocessing steps, linear contrasts employing canonical hemodynamic response functions were used to estimate amygdala habituation as the linear decrease over successive face matching blocks (i.e., block 1 > block 2 > block 3 > block 4). Follow-up analyses evaluated amygdala response differences in block 1 across genotype groups. Individual contrast images (i.e., weighted sum of beta images) were used in second-level random effects models accounting for scan-to-scan and participant-to-participant variability to determine mean contrast-specific responses using one-sample t-tests. A voxel-level statistical threshold of P < 0.05, family wise error corrected for multiple comparisons across the bilateral amygdala regions of interest, and a cluster-level extent threshold of 10 contiguous voxels was applied to these analyses. The bilateral amygdala regions of interest (ROI) were defined using the AAL template. BOLD parameter estimates from maximal voxels in the right and left amygdala ROI exhibiting a main effect for the amygdala habituation contrast were extracted using the VOI tool in SPM8 and exported for regression analyses in SPSS (v.22). Extracting parameter estimates from clusters activated by our fMRI paradigm, rather than those
